Dicarbonyl compounds in the synthesis of heterocycles under green conditions

Carbon–carbon and carbon-heteroatom bond forming reactions are strategically employed for the generation of a variety of heterocyclic systems. This class of compounds represents the most general structural unit, present in many natural compounds. They are recognized for their valuable biologically properties and wide range of applications in medicinal, pharmaceutical, and other related fields of chemistry. This is an updated review on the use of dicarbonyl compounds under environmentally friendly conditions to access a series of heterocyclic structures, e.g., quinoxaline, quinazolinones, benzochalcogenazoles, indoles, among others. Synthetic protocols involving copper-catalyzed, multicomponent and cascade reactions, decarboxylative cyclization, recycling of CO2, and electrochemical approaches are presented and discussed.

Bifunctional acidic ionic liquids-catalyzed decarboxylative cascade synthesis of quinoxalines in water under ambient conditions

An acid-functionalized ionic liquids (ILs) catalyzed cascade decarboxylative cyclization of 2-arylanilines with α-oxocarboxylic acids was developed. This approach offered a sustainable and practical pathway to afford a library of quinoxalines...

Palladium-Catalyzed Heck/[4+1] Decarboxylative Cyclization Cascade to Access Diverse Heteropolycycles by α-Bromoacrylic Acids as C1 Insertion Units

A novel palladium-catalyzed Heck/[4+1] decarboxylative cyclization cascade of alkene-tethered aryl iodides with α-bromoacrylic acids is reported. This strategy employs α-bromoacrylic acids as a new C1 synthon to assemble diverse heteropolycycles,...